# Monthly Archives: May 2009

## convex hull for recipes

If you enjoy cooking, this might ruin the fun. Hopefully not.

Much of the science of cooking depends on getting the proportions right. When I wing it in the kitchen (as I often do), I always keep proportions in mind. Over the years, I have developed an intuitive understanding of the sensitivity of recipe ingredient amounts, and I carefully measure only the most sensitive ingredients when cooking.

I just stumbled across a post that looks at the science of recipe ingredient sensitivity. A blog by a French geek explains how to find a convex hull for recipe ingredients in order to understand the sensitivity of the ingredients. The example provided looks at various recipes for crepes (image below is courtesy of Verisoning). The post is worth a read–it deepened my understanding of convex hulls. It even provides an interactive convex hull.   It doesn’t provide the optimal crepe recipe, however.  Link.

How do you use OR in the kitchen?

Convex hull for crepes recipes

## Brenda Dietrich shows that OR is creative

Who says mathematical modeling can’t be creative? IBM‘s Brenda Dietrich (OR extraordinaire) was selected as #27 on Fast Company’s list of The 100 Most Creative People in Business. She finished ahead of many celebrities, including children’s book author/illustrator Maurice Sendak (who wrote Where the Wild Things Are and my personal favorite Chicken Soup with Rice, which I can recite from memory), Neil Gaiman, Tyra Banks, and Brian Eno. Amazing! I tip my hat to Brenda Dietrich.

Update on 5/29.

For more about Brenda Dietrich and her division in IBM:

## should it stay or should it go? –> my impending office move

My department is moving to another building on campus next week. I have to pack up everything in my office this week in anticipation of the move. Although finding time to pack during finals week is not easy, I am enjoying rediscovering things that are in my office.

Things I will take with me

• My slinky (it’s an old school metal one)
• A commemorative 50th anniversary Management Science CD
• Floppy disks (I haven’t yet accepted the fact that I will never access these again, but I have some old work saved on these, so it seems wrong to throw them out)
• A zip disc (I had forgotten that these existed!)
• My daughter’s drawing of the two of us riding the elevator to my office (I think it’s a masterpiece)
• Chicago Bears playing cards (useful for low-tech random examples)

Things I am throwing out

• Chop sticks
• Lipton tea bags (I now keep a healthy stash of Bigelow teas in my office and can no longer stomach Lipton)
• Most of the post-it notes stuck to my computer monitor with “important” notes that, in retrospect, aren’t
• My emergency Sudafed (to be fair, I would be taking my Sudafed with me but I need it today for a nasty cold)

## not too sore to type

I ran a marathon yesterday. Despite the rain and the dismal crowds, I did great. Today, I am sore and my brain is tired. The race was particularly well-organized for such a small race (~200 full marathon runners). I wonder how OR has been used for races.

In March, I ran The Monument Avenue 10K here in Richmond with >30,000 runners. Historically, people just lined up according to anticipated race time, the race started, and we all ran. Last year, it felt like I spent a lot of time and effort passing people.

This year, the start line for the 10K began in waves, with walkers starting about an hour and a half after elite runners (Your time doesn’t “start” until the RFID chip you tie to your shoelaces is detected by the sensors as you pass the start line). They actually had bouncers enforcing the rules.  Needless to say, I got off to a fast start and encountered fewer other runners along the way. It was still crowded, but it was easy to pass other runners. I probably had my best race performance ever. (Runners: this is the most fun I ever have at a race. Run this one, if you ever have the chance. Winning the costume contest is tough–watch this year’s winner).

Clearly, OR is needed for big races to manage the start line, hand out water, determine how much water and Powerade is needed, plan for adequate parking, determine the width of the route, etc. But in my experience, OR is critical for small races, too.

If you have organized a race, how have you used (or should have used) OR?

## random thoughts of a quantitative nature

Just organizing a few thoughts regarding computational complexity, applied probability, and cost-benefit analysis.

• A song called “I just do theory” [mp3] made me smile. (“I wrote a program that solved TSP / Superquasipolynomially / Ain’t no such thing as lunch for free / When you’re digesting P-NP”). Link for lyrics.
• One of the players that the Chicago Bears drafted this week (Al Afalava) boasts that he won a Rocks-Paper-Scissors tournament. His odds of winning are probably 1/N. Before you start arguing that there is skill involved, consider this: he lost in the first round following his championship run. Link.
• Carl Bialik reports that often, poker is a game of chance, not a game of skill. Of course, skill is really important, but the article is worth a read. Link.
• A geeky mother provides a cost-benefit analysis of breastfeeding in response to a recent Atlantic article that slams breastfeeding (I felt like the Atlantic article brought up a couple of good points, but I was otherwise unimpressed). Many, many differening opinions have been voiced. This is the quantitative response I would have written if I had more time. Link.